1. Field of the Invention
The present invention relates to acrylic polymers, and methods of preparing and using the same. More specifically, the present invention relates to acrylic polymers containing N-methylol-amide group, an amino group, and an acid group. These polymers are particularly useful in ink compositions.
2. Brief Description of the Prior Art
Acrylic polymers containing copolymers comprising N-methylol groups are known in the art. Also known in the art are acrylic polymers comprising copolymers which contain N-methylol groups and amino groups. The N-methylol groups are known to be highly reactive and susceptible to self-condensation and reaction with other sources of active hydrogen, particularly in the presence of acid groups. Consequently, compositions containing N-methylol groups can react prematurely and undesirably to form gelled compositions or otherwise become ineffective for their intended use. Hence, the art has seemingly stayed clear of preparing acrylic polymers which contain a significant amount methylol group, and acid groups in the polymer matrix.
By the present invention however, acrylic polymers containing N-methylol groups and acid groups have been prepared in such a manner as prevents or at least reduces the premature reaction and consequential gelation of compositions comprising such acrylic polymers.